Indica vs. Sativa: What Gives Indica Its Sedative Properties?

A recent analysis of the High Times Cannabis Cup strain database has found that sativa-dominant plants are more likely to have higher amounts of myrcene, sometimes up to double that of the average indica. Contrary to what other sources say, myrcene might not be responsible for the “couch-lock” effect in indicas.

On the outside, telling the difference between a sativa and and an indica boils down to how the plant grows; short and stocky plants with dense buds are indicas, and sativas grow tall and lanky with spindly buds. The geographical origin of each lineage explains the difference in how they grow, but what explains the difference in their varying effects?

As medical research into the different components of cannabis progresses, more credit is being given to the role of terpenes. Volatile, liquid substances at room temperature, terpenes comprise the essential oils of many plants, and cannabis oil has almost 100 terpenoid compounds.

When it comes to the matter of using terpenes to rationalize the difference of effects between strains, only about six are present in large enough quantities to be considered candidates. As a recognized sedative, it seems logical to propose that myrcene is the one responsible for couch-lock in indicas… but does the data really match this theory?

A comparison of the terpenoid profiles of past Cannabis Cup entrants says otherwise.

This table shows the average content of different terpenes by mg/g in flowers entrants in either indica or sativa categories. Sativas have higher myrcene and terpinolene, while linalool, limonene and caryophyllene predominate in the indicas.

Steep Hill labs, which coincidentally has done some of the testing for the Cannabis Cups, says that any strain with more than 0.5% myrcene is an indica and anything less is a sativa. Amongst our pool of data, a strain in the sativa category was one-and-a-half times more likely to have higher than 0.5% myrcene.

The genealogy of every strain placed into either indica or sativa categories of the Cannabis Cup is analyzed to assure its identity. If a strain doesn’t show dominance from either branch, it gets put into the hybrid category. Needless to say, the hybrid category is always the largest. This vetting process levels the playing field for every category and assures the quality of data we extract from the competition.

Well-known sativas like Hawaiian Dutch and Durban Poison had the highest myrcene content at 1.6% and 1.5% respectively. Super Silver Haze also tested at 1.4% myrcene.

An earlier tetrahydrocannabivarin (THCV) analysis comparing sativa and indica entrants in the Cannabis Cup showed a higher content of this potent cannabinoid in sativa strains. THCV has a shorter non-polar side-chain, which increases water solubility. High levels of this quick-moving cannabinoid could explain the punch-you-in-the-face effect of some potent sativa-dominant strains.

It would appear that something else is going on with myrcene in marijuana. Myrcene may have sedative properties when administered orally in sufficient amounts, but this doesn’t mean you can achieve these effects from consuming a myrcene-heavy bud. The smoke around this issue will clear as more headway is made into chemo-profiling cannabis strains.